Lightweight block, heavyweight benefits
By Don Eberly
Six constructed block warehouses at the Maryland Science Center in Baltimore are a testament to on-time and on-budget delivery. Built by St. John Properties, the buildings provided the center with a distinct advantage, both in the way they were constructed and the resources used – time, labor and materials.
The project called for six new warehouse buildings to be constructed on a section of the property about 300 yards from existing buildings. The warehouses were to be rented out for storage to a high-profile tenant with a strict timeline. The buildings had to go up quickly to fill the demand.
Knowing that constructing such a large project in an expedited situation would come with its share of budget concerns, the contractor for St. Johns Properties turned to Ernest Maier Inc., a local block, masonry and hardscaping supply company, for a solution. As a manufacturer of normal weight masonry units, Ernest Maier already had been working with Big River Industries Inc., a producer of expanded clay lightweight aggregate. Brendan Quinn, owner/president and CEO of Ernest Maier, knew that lightweight masonry block would fill the need for a fast turnaround in construction, while staying within the project’s budget.
The units contain Big River Industries’ expanded clay lightweight aggregate, called Riverlite, which makes them lighter and, ultimately, reduces labor and time in construction.
“Lightweight block increases productivity even at the same labor pace,” says Quinn, “and workers are typically more efficient, because the lighter block is less work intensive.
Get in, get outAs a result, the contractor used E-lite 24-inch-long lightweight concrete masonry units, supplied from Ernest Maier, in place of the standard weight 16-inch gray units. In doing so, he reduced construction time and labor specific to this part of the project by 50 percent. In all, 6,600 24-inch-long lightweight units were used for the straight walls and corridors of each of the four 75,000-square-foot buildings at the Maryland Science Center. The mason also used several 12-inch lightweight units and a variety of normal weight material for other applications within the job.
Using lightweight block worked within the building’s budget, the mason found, and he benefited from using this alternative in several ways. In addition to getting paid by the square foot, he also made money for completing the job faster. His crew was better off for using lighter weight units and avoiding common injuries associated with heavier block.
According to Jeff Speck, VP of sales and marketing with Big River Industries Inc., these are the key benefits of using lightweight masonry units, especially in large jobs like warehouse construction.
“The lightweight factor helps contractors complete projects sooner, so they can generate revenue from the projects earlier, which is better for the property owners as well,” says Speck. “In construction, we all known time is money, and if property owners can reduce the number of days it takes to construct a building, it helps them project when it can be rented and begin earning revenue.”
What makes lightweight units lighter?The E-Lite units used for the buildings contain 60 percent Riverlite, 28 percent natural aggregates, and the rest is cement and water. The finest gradation of the expanded clay lightweight aggregate (LWA) qualifies as a reclaimed material, which is a benefit for contractors applying for Leadership in Energy and Environmental Design (LEED) credits.
Together with its sister companies, Parker Block in Delaware and Skyline Brick in Virginia, the Maryland-based Ernest Maier produces millions of units annually, ranging from standard weight to extra light. A good portion of its products contain expanded clay LWA, produced at Big River Industries’s Southeastern facilities.
The quality of the expanded clay LWA results from a carefully controlled manufacturing process. “In a rotary kiln, selectively mined clay is fired in excess of 2,000 degrees Fahrenheit,” says Speck. “The clay expands, cools and is then processed to specified grading.”
The result is a high-quality, lightweight aggregate that is inert, durable, tough, stable, highly insulative and free-draining to meet stringent structural specifications.
Familiarizing with the process by studying Big River Industries’s Q-Lite units, Ernest Maier developed its E-Lite block to provide customers like St. John Properties with a unique approach to time, labor and cost savings.
“The lightweight units have better thermal properties, saving property owners money on heating and cooling,” Speck says. “Additionally, they have superior fire resistance, providing more structural stability, which is an improvement over regular weight material; and, they’re safer to handle.”
Productivity is criticalDespite all the benefits using lightweight block offers, most construction projects are ruled by the budget and the bottom line, according to Quinn.
“Even though it makes complete sense to use a lighter weight option, it is tough to persuade some architects and contractors to do it because of the upfront price tag,” Quinn says. “But, the savings is realized in the end.”
In masonry construction, the cost of labor has evolved, with legal labor in the $12 to $13 per hour range, and up. Inflation rates can cause contractors to refrain from spending more for materials.
“But, with labor costing at least 50 percent of many masonry unit projects, the 50 percent labor savings that is attainable by using 24-inch-long lightweight units more than pays for the additional upfront product cost,” Quinn says. “Block is only 10 percent of what makes up many masonry contracts.
“For instance, with a $2 million project, the cost of the block could be approximately $200,000,” he continues. “Labor makes up 50 percent of the costs. If you can take a variable cost like that and improve it, the overall cost of the project will go down.”
In the case of the Maryland Science Center warehouses, the mason was handling 24-inch-long units, which weigh the equivalent of 16-inch-long normal weight units. He gained 50 percent more wall area by placing the same number of units, at the same labor pace.
To assist in pre-planning the upfront product costs versus ROI, Quinn provided detailed spreadsheets to the project planners, providing line item descriptions for the costs and savings they would realize by using the lightweight alternative. From there, he worked with the Maryland Science Center warehouse project team on a strategy to keep costs aligned with the budget.
Learning not taken lightlyThough the technical components of using lightweight block are easier because it weighs less, the longer, 24-inch units did cause a slight learning curve for the mason on the Maryland Science Center site. The cores of the 24-inch units are larger, because they are longer; filling the cores requires more grout. Thus, the mason came up with a way to reduce the grout volume.
Ernest Maier offers classroom education at its Maryland facility to advance learning about lightweight concrete masonry and the related benefits and applications for architects and contractors nationwide. This education will include masonry techniques for lightweight block, such as grouting for larger sized units and other matters.
One of the reasons Ernest Maier’s E-Lite block was chosen in the Maryland Science Center project was for the company’s familiarity with the masonry industry and needs in the area. The business also earned one of the highest honors with a visit from President Barack Obama, who was touring manufacturers’ facilities at the time to generate growing interest in the construction industry. Quinn believes that providing education and awareness about new products, related techniques and industry topics, is paramount to success.
Safety and savings, hand-in-handAccording to Speck, aside from the 50 percent labor savings that the 24-inch-long lightweight units can provide, using them also takes safety programs and corporate accountability to another level.
“If employers treat masons well, as the productive members of the company who they are, using lightweight block is a long-term investment in the ethical treatment of employees,” Speck says.
By thinking in terms of money that can be saved from having fewer back injuries and workers’ compensation claims, contractors stand the chance of decreasing significant relational costs of projects.
“A contractor once told me that one back injury costs his company more money than the difference in the price of normal weight block versus lightweight block,” Speck says. “That savings would buy lightweight block for two years.”
When it comes to initial product selections, preliminary costs and the possible eventual outcomes surrounding masonry projects such as this one, thinking long term might very well yield the highest level of profitability.
Originally published in Masonry magazine.
About the Author
Don Eberly is the co-owner of Eberly & Collard Public Relations.